Drill Sergeant Nasty: The commander who pops up in the briefings of a few levels such as Strange Sightings, Explosive Connections and (in the Deluxe rerelease) UFO Rescue.
If you use this cheat on one of the "Train Park" jobs with no objectives, instead of a standard "Congratulations!" message you usually get on other jobs, you get a low quality "placeholder" voice clip which says "Briefing.
Developer's Foresight: One of the cheat codes involves forcing the current job to be labeled as complete.
Cool Train: Kinda obvious given the concept, but the train featured on the moon levels is a futuristic looking train which goes very fast on the highest speed setting.
Deluxe's job editor includes the option to change the default captions with your own.
Caption Humor: Some of the descriptions of objects.
Bigfoot, Sasquatch, and Yeti: The goal of the final job of the Fire Stoker difficulty involves building a jungle gym (which looks like the Eiffel Tower) for a yeti that lives in the North Pole.
Annoying Younger Sibling: The "Little Sister" set of jobs.
All Deserts Have Cacti: The titular Cactus Valley location.
Aliens Steal Cattle: If a job in Cactus Valley has a cattle farm somewhere in the level, there's a small chance a UFO will come and abduct one.
Advanced Tech 2000: The Switchy 5000, a device used in two jobs that switches tracks every time a train crosses over it.
3-D Ultra Lionel Traintown contains the following examples of: